Multiple-switch starter.



- E. BARNUM. MULTIPLE SWITCH STARTER. APPLICATION FILED JULY 26, 1909.

959,910, Patented May 31,1910. 2 SHEETS- 8111531 1.

T. E. BARNUM. I MULTIPLE SWITCH STARTER.

APPLICATION FILED JULY 26, 1909.

Patented May 31, 1910.

2 SHEETS-SHEET 2 TKOILS E. BAZBNUI, OF MILWAUKEE, WISCONSIN,

ASSIGNOR TO THE CUTLER- IFG. CO., OF MILWAUKEE, WISCONSIN, A CORPORATIONOF WISCONSIN.

MULTIPLE-SWITCH STARTER.

Specification of Letters Patent.

Patented May 31, 1910.

Application filed July 26, 1909. Serial in. 509,537.

To all whom it may concern:

Be it known that I, THOMAS E. BARNUM, a citizen of the UnitedStates,residing at Milwaukee, in the county of Milwaukee and State ofWisconsin, have invented new and useful Improvements in Multiple SwitchStarters, of which the following is a full, clear, concise, and exactdescription, reference being had to the accompan mgdrawing, forming apart of this spec cation.

My invention relates to improvements 111 multiple switch devicesparticularly appropriate for starting electric motors. I

More particularly, my invention relates to multiple switch devices inwhich each switch, when closed, is arranged to hold a preceding switchclosed. This arrangement enables the switches to be closed" by ahand-overhand movement. In such devices it is desirable to arrange theswitches so that they will have a tendency to move into open position.Consequently, if each switch is held closed under the pressure ofanother switch, each switch, and particularly the last switch of thesequence, will be placed under a considerable strain due to the tendencyof the several switches to move to open position. This not only rendersit difficult for the operator to close the switches in the predeterminedorder, but also tends to cause the release of all of the switches if thelast opertion. .That is to say, if the pressure upon the last operatedswitch is momentarily de creased, all of the s d switches have atendency to immediately return to open position. Even though theswitches do not have an opportunity to open, yet they are apt to movesufl'iciently to prevent closure 0 the remaining switches. This, ofcourse, necessitates reciosure of all of the switches.

It is, therefore, the object of my invention to rovide means forpositively locking each switch in closed position in such a manner thatpractically no pressure upon any of the switches will be required tohold the precedin switches closed. Consequently, there wil bepractically no strain upon any of the switches due to the tendency ofpreceding switches to move to open position.

Various other objects and advantages of my invention will be hereinaftermore fully set forth.

In order to more clearly disclose the nature of my invention, I shalldescribe the embodiment thereof illustrated in the accompanylng drawing.It should, of course, be understood that my invention is not limited tothe exact construction shown in the drawing, but is capable of variousmodifications.

In the accompanying drawing, Figure 1 is a front elevation of one formof my invention; Fig. 2 is a sectional view taken on line 2-2, Fig. 1;and Fig. 3 is a sectional view taken on line 33, Fig. 1.

In the embodiment of my invention illustrated, I have shown fourswitches 1, 2, 3 and 4, it, of course, being understood that the numberof switches may be increased or decreased as desired. Each of theswitches is of substantially the same construction and I shall,therefore, describe only one of the same in detail. The construction ofthe several switches is best illustrated in Fig. 2. Each switch includesa switch arm 5 fulcrumed on a pin 6. In practice, the several switcharms might be fulcrumed upon a single rod, but, in the present instance,I have shown an individual supporting bracket 7 for each of the switcharms. The bracket 7 merely comprises a plate 8, adapted to be secured toa suitable insulating anel 9, said plate having perpendicular si epieces 10. The pin 6 is preferably supported by the side pieces 10 ofthe bracket. The switch arm carries a laminated contact brush 11, oneend of which is adapted to engage a contact plate 12, and the other endof which is adapted to engage a-contact plate 13. In practice, thecontact plates 12 of the several switches are preferably formedintegrally as illustrated in Fig. 1. In addition to the laminatedcontact, the switch arm carries a pivoted extension 14, upon the end ofwhich is secured an arcing contact 15. The arcing contact 15 is adaptedto engage a carbon contact 16 which may be mounted in any suitablemanner and electrically connected to the contact late 13. Connected tothe switch arm 5 an passing through the pivoted extension 14 thereof isa pin 17 carrying a co lar 18. Interposed between the collar 18 and theextension 14 is a coiled spring 19 which tends to hold the extension 14in such position that the arcing contact will engage the carboncontactbefore the laminated brush engages its stationary contacts.

The switch arm is provided with an acswitch arm. The switch arm has anexten-.

sion 22 which is connected by links 23 to the supporting bracket 7, thelinks 23 being fulcrumed to both the extension and the bracket. Thisconnection, in effect, forms a toggle whereby, when the operating lever20 is forced inwardly, it forces the switch arm 5 in the same direction.With the particular arrangement illustrated, each of the switches tendsto automatically return to initial position without the aid of anyspecial spring for this purpose. This tendency is increased by thespring 18 and the resiliency of the laminated brush. As the switch armisada ted to fall outwardly with some force, I preferably provide thesame with a spring buffer 24 adapted to engage the extension 22 of theoperating lever. The operating lever of each switch, except the last ofthe sequence, is provided with a laterally extendin lug 25 projectingfrom the right hand side thereof. These lugs are best illustrated inFig. 1. The lug 25 is arranged, to be engaged by a pivoted latch 26 tohold the switch which carries said lug in closed position. The functionof the lug 25 and the latch 26 is illustrated in Fig. 2, it beingunderstood that the lug and latch illustrated therein belong to theswitch 1. The latch 26 is fulcrumed on the rod 6 to the right of theswitch arm and normally stands in the position illustrated in Fig. 3,the downward movement thereof being limited by a stop 27 adapted toengage the bracket 7. Thus in normal position, the latch will not engagethe lug 25 to hold the switch closed. It, therefore, becomes necessaryto raise the latch 26 in order to lock the switch in closed position.For accomplishing this result, I have provided on the left hand side ofeach switch, except the first, a laterally extending la 30, adapted toengage the underside of the latch of the next preceding switch. Theunderside of the latch 26 is preferably so curved that. when the lug 30is forced inwardly it will raise said latch into the path of the lug 25.

Owing to the connection between the op- 'erating lever and the switcharm when the switch is open, the lug 25 will engage the front end of thelatch 26 as illustrated in Fig. 3. Furthermore, the enlarged portion 31of the liig 30 of the next succeeding switch will engage the lug 25.This arrangement, as will be hereinafter inore clearly set forth, formsan interlock for preventing closure of the switches, except in apredetermined sequence.

I shall now describe the operation of the switches. In Fig. 1, I haveshown switches 1 and 2 in closed position and switches 3 and 4 in openposition. Let it be assumed,

however, that all of the switches are open. Under these conditions, allof the switches would be in the osition illustrated in full lines inFig. 3. onsequently, the lug 25 of switch 1 would be disposed betweenits latch 26 and the lug 30 of switch 2, as shown in Fig. 3. If new itbe attempted to close the switch 2 before closing the switch 1, it willbe found that movement of the switch 2 is blocked by the lug 25 ofswitch 1. Assuming, however, that the operating lever of switch 2 couldbe moved into the position shown in dotted lines, thereby forcing theoperating lever of switch 1 into such a position that its lug 25 wouldassume the position shown in the dotted lines, then further movement ofsaid lever would be absolutely blocked, as the latch 26 virtually formsa wedge between the lugs 25 and 30. It is not likely that switch 2 couldbe moved into this position, but, even if such movement was possible,said switch would not be closed. The lugs on the remaining switches coopcrate in a similar manner, and it is, therefore, apparent that theswitches must be closed successively, beginning with switch 1.

Let it now be assumed that switch 1 is first moved to closed position.This results in moving the lug 25, carried thereby, into the positionshown in Fig. 2, the latch 26, however, remaining in the position shownin Fig. 3, thereby leaving the switch 1 free to return to initialposition. Upon closure of the switch 2, however, the lug 30, carriedthereby, engages and raises the latch 26 of switch 1 into the positionillustrated in Fig. 2. This positively locks the switch 1 in closedposition and the same may thereupon be released. The lug 30 of switch 2merely supports the latch 26, and, consequently, after said switch 2 isclosed, practically no pressure is required to hold the switch 1 inclosed position. Upon closure of switch 2 the lug 25, carriedthereby, ismoved into the position shown in Fig. 2, the latch 26 thereof remainingin the position shown in Fig. 3. Upon closure of switch 3 the lug 3Qthereof engages the latch 26 of switch 2 and moves the same upwardlyinto the path of the lug 25 of said switch 2 as illustrated in Fig. 2.Again, closure of the switch 3 moves its lug 25 into the position shownin Fig. 2, while the switch 4, when closed, raises the latch 26 of theswitch 3 into the path of its lug 25', thereby locking said switch 3 inclosed position.

For holding the switch 4: in closed position, I have shown a retainingmagnet 32, having a pivoted armature 33, provided with a hooked portion34:, adapted to engage a pin 35 projecting laterally from the switch a.In practice, the magnet 32 might be of the low voltage type, so that ifthe voltage failed for any reason, it would release switch 4, whichwould then fall to open position. The opening of the switch 4 wouldrelease the latch of switch 3, thereby permitting the latter switch toopen. Switch 3 in opening would release switch 2 and switch 2, inopening, would release switch 1, thereby permitting all of said switchesto return to open position.

With the arran ement illustrated, it will be seen that instea of eachswitch holding a preceding switch closed, by pressure, each switch ispositively locked in closed position, and its succeeding switch ismerely required to retain its latch in holding position.

Having thus described my invention, what I claim and'desire to secure byLetters Patent, is

1. In combination, a plurality of switches tending to stand inopenposition, and a plurality of latches for holding said switches 20 inclosed position, said latches tending to move into a position to releasesaid switches, and each of said switches being adapted, when closed, toretain the latch of a preceding switch in holding position.

2. In combination, a plurality of switches tending to stand in openposition, and a plurality of latches for holding said switches in closedposition, said latches tending to stand in position to release saidswitches, and each of said switches, when closed, being adapted to movethe latch of a preceding switch into holding position.

3. In combination, a plurality of switches tending to stand in openposition, and a plurality of latches for holding said switches in closedposition, said latches tending to move into position to release saidswitches and to insure closure of said switches in a definite sequence,and each of said switches being adapted, when closed, to retain thelatch of a preceding switch in holding position.

4:. In combination, a plurality of switches tending to. stand in openposition, and a plurality of latches for holding said switches in closedposition, said latches tending to move into position to release saidswitches and to insure closure of said switches in a definite sequence,and each of said switches being adapted, when closed, to move the latchof a preceding switch into holding position.

5. In combination, a plurality of switches tending to stand in openposition, a plurality of latches for holding said switches in closedposition, said latches tending to move into position to release saidswitches, and to insure'closure of said switches in a definite sequence,each of said switches being adapted, when closed, to retain the latch ofa preceding switch in holding position, and an electroma et forretaining the latch of the last switc of the sequence in holdingposition.

6. In combination, a plurality of switches tending to stand in openposition, a plurality of latches for holding said switches in closedposition, said latches in normal position being adapted to release saidswitches, and lugs on said switches arranged to cooperate with saidlatches to necessitate closure of said switches in a definite sequence,a lug on each switch being arranged to maintain the latch of a precedingswitch in holding position.

7. In combination, a plurality of switches tending to stand in openposition, a plurality of latches for holding said switches in closedosition, said latches in normal position being adapted to release saidswitches, and lugs on said switches arran ed to cooperate with saidlatches, when in normal position, to necessitate closure of saidswitches ina definite sequence, one of the lugs on each switch beingadapted to move the latch of a preceding switch into holding position.

8. In combination, a plurality of switches tending to stand in openposition, a plurality of latches tending tostand in position to preventthe closure of all, but one of said switches, each switch being ada ted,when closed, to render one of said atches ineffective to retard theoperation of a succeeding switch and to retain another latch in positionto hold a preceding switch closed.

9. In combination, a plurality of switches tendin to stand in openposition, a latch for ho ding each switch in closed position, each ofsaid latches having a tendency to release its correspondin switch, and alug on each switch for retaining the latch of a preceding switch inclosed position, each latch being arranged to prevent closure of asucceeding switch while its corresponding switch remains open.

10. In combination, a plurality of switches tending to stand in openposition, an operating lever for each switch having a to gle connectiontherewith, a plurality of latc es, a locking lug arranged on theoperating lever of each switch to be engaged by one of said latches,another lug on the operating lever of each switch for retaining one ofsaid latches in engagement with the locking lug of a preceding switch,said latches tending to release said switches, and being arranged tocooperate'with said lugs to insure the closure of said switches in adefinite sequence.

In witness whereof, I have hereunto subscribed my name in the presenceof two witnesses.

THOMAS E. BARNUM. Witnesses:

FRANK H. HUBBARD, S. W. FITZGERALD.

